Shorepower Charger and Combiner

[macbeth]

[QUOTE=Mark Johnson;701200, I can switch the engine "cranking option" three way switch from eng. battery to house battery, to crank the engine. In 15 years I haven't needed to.

I ALSO have a three way switch to run the boat off of the house batteries, (like normal), OR the engine battery.


Mark[/QUOTE]

Q1. Is the engine "cranking option" three way switch the normal "Off,1, Both, 2" switch ?

Q2. If yes to Q1, I'm not sure I see the purpose of the second switch. Could you please clarify/expand.

Thanks.

[macbeth]

If the alternator is connected to the House battery, all the time, is there an opportunity for leaks to occur, causing, in the long run, a flat House battery ?

Currently, my distribution board for the house circuits is attached to the input terminal of the starter. (which can be connected to either Engine battery or house battery by means of the "Off,1,both,2" switch.)

Assuming I changed the alternator return cable to be attached to the House battery PERMANENTLY I guess I could change distribution board to the output of the alternator, thus becoming connected to the alternator battery ? Only problem here is that it seems to me that somehow one should be able to turn off ALL house circuits from one switch ?

How would I cover the case of accidentally turning the Off, 1, both, 2 switch to OFF while the engine was working ?

I guess what I'm trying to design is a system that allows me:
1) to switch the starter to either Bat1 (engine) or Bat2 (house), separately or combined,

2) Dedicate the house circuits to Bat2

3) Avoid the possibility of having no return from the alternator when the engine is running.

All without massive changes to my current layout !

Any design suggestions ??!!

[redcobra]

Originally Posted by macbeth

If the starting battery happens to be flat, it seems to me that the combination feature would make the house battery current flow to the starting battery, until you ended up with both batteries at half charge (or worse), before you could push the start button !

???
How long do you think it takes for 100AH of current to flow from one battery to another.
Takes 2 seconds to flip the switch and hit the button.

My simplified boat electrical attached.

[macbeth]

Originally Posted by redcobra

???
How long do you think it takes for 100AH of current to flow from one battery to another.
Takes 2 seconds to flip the switch and hit the button.

Takes more than 2 seconds for me to get from the switch to the button !

It's the principle that matters, not the practice.

[redcobra]

Originally Posted by macbeth

Takes more than 2 seconds for me to get from the switch to the button !

It's the principle that matters, not the practice.

Don't be silly. The switches are 4 ft. apart.

See my boat electrical above.

ps: It would take at least an hour to move 100AH from one battery bank to another (Ah=the electric charge transferred by a steady current of one ampere for one hour) using lead acid batteries and heavy cables. And, if the house bank is 430Ah and the starting battery is 100Ah. It's a moot point as when the engine starts the alternator kicks in.
Yes, you should switch back to single circuit from combine when the engine starts, but you don't have to.

[osirissail]

Originally Posted by macbeth

. . .
1) to switch the starter to either Bat1 (engine) or Bat2 (house), separately or combined,
2) Dedicate the house circuits to Bat2
3) Avoid the possibility of having no return from the alternator when the engine is running.
All without massive changes to my current layout !
Any design suggestions ??!!

Okay, when designing an electrical system for a vessel, especially a sailboat the number 1 and massively overriding consideration is SAFETY. Convenience and everything else takes a back seat. If you are out away from shore any further than you are comfortable swimming back, you do not want to be treading water as your boat burns to the waterline.
- - If you have a small boat with a simple DC system for lights and navigation and one battery, then you only need a properly rated "on/off" battery switch. Everything is wired from the output of that battery switch to whatever distribution panel w/C/B's you have.
- - The overriding purpose of the battery switch is SAFETY - the ability to disconnect the battery(s) from all loads quickly and completely in case of an emergency (e.g. electrical fire).
- - As boats get bigger and the electrical systems more complex you need to maintain the ability to disconnect the battery(s) from all electrical systems using the battery switch (es). Anything else is inviting an opportunity for that long swim back to shore.
- - Maintaining the integrity of the SAFETY function of the Battery Switch(s) is difficult sometimes when things like SSB's and other major loads beg for "direct access" to the battery(s).
- - When it comes to engine starting - the same SAFETY concerns require that nothing be attached to the engine starting battery except the actual engine starter. If you are peacefully anchored and a threat appears like a drifting boat, or storm system with extreme gusts, being able to start the engine becomes a matter of life or death or at least preventing the loss or major damage to your vessel.
- - As batteries age or are improperly manufactured they build up deposits inside that eventually lead to an internal "Dead Short" and a potential for serious problems beyond just not being able to get any power from them.
- - Allowing a good battery to be connected to a shorted battery will virtually guarantee an electrical fire. If you have ever mistakenly touched a screw driver or other tool across the + and - terminals of a battery you will have observed how that tool was vaporized in an instant flash. Likewise, engine starters (mine especially) draw upwards of a thousand amps to start rotating. The only reason this works is that the time interval of the draw is for less than a second.
- - Being able to "combine" your house batteries to a dead shorted engine start battery or vice versa is something you do not want to be able to do. There are battery switches that do not contain a "both" position or you can modify a battery switch to prevent being able to use the "both" position.
- - Unless you are happy with swimming to shore while your boat burns, take some time to arrange your battery(s) switching systems to do what they are intended to do - stop an electrical fire from starting or continuing.

[Andina Marie]

Originally Posted by redcobra

I would get rid of the WM 150 as they are pretty old technology. I have had several fail.
Just my $0.02/

The WM 150 by West Marine was made by Yandina and comes with unlimited warranty so don't throw them away. They have twice the capacity of the cheaper ones.

[CharlieJ]

- - Allowing a good battery to be connected to a shorted battery will virtually guarantee an electrical fire. If you have ever mistakenly touched a screw driver or other tool across the + and - terminals of a battery you will have observed how that tool was vaporized in an instant flash. Likewise, engine starters (mine especially) draw upwards of a thousand amps to start rotating. The only reason this works is that the time interval of the draw is for less than a second.

Very true. The work around to eliminate the potential for this to occur is really quite simple and something that I have installed on many vessels; commercial, private, power and sail.

First, put an ON-OFF switch (Switch 1) (or solenoid) in the B+ supply from the starting battery to the starter.
Next, put an ON-OFF switch (Switch 2) (or solenoid) in a new B+ conductor from the house battery that terminates on the load side of Switch 1.
That's it!

Starting battery goes flat or totally fails; open Switch 1 and close Switch 2. With solenoids such as the Blue Sea ML Series of magnetic latching remote battery switches, this sequencing can be handled with a single toggle switch at the helm. Normal operation: Solenoid 1 shut, Solenoid 2 open. Emergency operation: Solenoid 1 open, Solenoid 2 shut.

Works great.

Charlie

[goboatingnow]

orisisail, you must of never heard of battery fuses!

DAve

[doug86]

Originally Posted by osirissail

- - Unless you are happy with swimming to shore while your boat burns, take some time to arrange your battery(s) switching systems to do what they are intended to do - stop an electrical fire from starting or continuing.

If only....

here is pic of a main battery switch that was melted so bad that we couldn't use it to disconnect the batteries, about 1 minute after a wrench accidentally connected the main alternator tap to ground. The wrench had to be removed with a grinder after the fire was put out. Notice the charred wiring in the background? This is all in the main panel, the real short was back in the engine room, where the wiring loom was one giant melted mess.

Battery disconnect switches will not survive a dead short for very long, so don't count on them to provide an ounce of fire safety. Fuses are what stop shorts, not switches.

I took this picture after I put the fire out while the USCG stood on deck and handed me fire extinguishers, while my associate found the batteries and cut the main wires.

[goboatingnow]

Most battery switches are on boats to facilitate routine battery disconnection so as to prevent discharge. Safety is a secondary concern as if it were not so then all switches would be accessible from outside.

If you want safety use battery fuses, not switches. It's why modern cars all have fused batteries but none have switches.

Dave

[osirissail]

Originally Posted by goboatingnow

orisisail, you must of never heard of battery fuses!
DAve

Quite to the contrary. I have been a major proponent and installer of buss fuses for the main battery feeds long before ABYC and others advocated them. Fact is, until ABYC started recently requiring them we had numerous electrical fires due to stuck starter solenoids and other major shorts.
- - As to main battery feed switches, it is all too common that for a grossly inadequate sized switch to be used. Mostly as the price of a serious battery switch is considerably higher.
- - There is no end to sloppy and improper fabrication of vessel electrical systems. And it will probably continue into the future despite the efforts of ABYC and others. Proper protection by the use of terminal covers, and shields is often defeated by lazy and slap dash repairs or installations by boat owners and/or small marine electricians trying to save money or increase their profit margins. You get what you pay for.
- - And now you will see ABYC standards requiring the use of main feed buss fuses on battery chargers, inverters and other high current loads all of which 20 years ago did not "require" such things. As more and more owners start "improving" their boats, we see more and more improper and downright dangerous electrical practices. It takes time and money to do it proper. Too many boaters think their boats are just floating houses and try to wire them according to house standards. That is a sure recipe for the long swim.

[macbeth]

Originally Posted by DeepFrz

Move the connection from the alternator to the house bank. The start battery typically requires very little recharging, although with the windlass connected to the start battery it will require a little more. The house bank is usually the one that needs the most charging time and amps.

The new Raymarine Autopilot I have just purchased recommends putting the instrument on a different circuit than the starter circuit. So I have just installed the relatively new two circuit (with Combine) switch from BlueSea. It works well, and saves me from having to worry about which battery I'm using at different times, e.g starting the engine, sailing, etc. Goodbye "Off-1-Both-2" switch.

I've connected the alternator to the House bank, as it's the larger bank (as recommended by Bluesea). It also needs more charging than the starter battery. This means I have less current (e.g. about 8 amps) flowing through the ACR/Combiner to the Starter battery, than had I connected the alternator to the starter battery (used to need about 80 amps flowing through the ACR/Combiner to the House battery). I've connected the Windgenerator and solar panel to the House battery as well. The windlass will stay on the starter battery to avoid any spikes or brown-outs to the Autopilot.

Although it has two outputs, I've connected the AC shore power charger to only the House battery for the same reason as explained in the previous paragraph. Also one less wire in the already complicated battery area.

All in all, I think I have a better battery installation than I had before.

[daddle]

Sounds good except for the windlass on the start battery. Without the 1-2-All-Off switch you'll have only the start battery to pull the anchor. No alternator helping. No large deep battery bank. Might work. Might not. The windlass annoying the instruments should not be any big deal as not much navigating is going on while the anchor is out.

[macbeth]

Originally Posted by daddle

Sounds good except for the windlass on the start battery. Without the 1-2-All-Off switch you'll have only the start battery to pull the anchor. No alternator helping. No large deep battery bank. Might work. Might not. The windlass annoying the instruments should not be any big deal as not much navigating is going on while the anchor is out.

Not so.

Actually about the only disadvantage I have realized is that its about 3.5 minutes after starting the engine before the ACR/Combiner starts flowing amps to the starter battery: 1.5 minutes delay before the smart charger will allow amps to flow to the House battery, then another 2 minutes before the ACR/Combiner will start to work. This doesn't mean I can't use the Windlass before that. Usually just means I start the engine and then get the Windlass remote control plugged in, and get other things ready before I push the Anchor Windlass UP button !

And then, of course, if really needed, there is the "Combine" position on the switch which would mean I'd have the pulling power of both House & Starter batteries immediately after turning the switch to that position.

It's not a case of the Windlass "annoying" the Autopilot, it's more a case of the Autopilot's Control/Display unit being blown by a spike, (as happened to a friend just lately).

If you haven't yet come across the dual circuit "Off-On-Combine" switch I recommend it.